SCOTTSDALE, Ariz. -- D-backs starter Trevor Cahill debuted his new mechanics for the first time in a game and pitched well, allowing two hits and one walk over two scoreless innings as the Rockies lost, 4-3, Thursday at Salt River Fields at Talking Stick.
Cahill, who struggled mightily last year and is competing for a spot in the rotation, has tweaked his mechanics to throw more over the top in hopes of improving his command.
Rockies starter Jhoulys Chacin, who was limited to just 11 starts last year due to a shoulder injury, retired the D-backs in order in the first inning before running into trouble in the second.
Mark Trumbo led off the second with a double, and one out later Cody Ross drove him home with a single to center. After Chacin was removed in favor of Jason Gurka, Ross wound up coming around to score on a single by Gerald Laird to give the D-backs a 2-0 lead.
"The mechanics stuff you can fix," Chacin said. "Other than that I feel fine."
Vidal Nuno, who is also competing for a spot in the D-backs rotation, did not fare as well as Cahill. The lefty allowed a pair of runs on five hits in two innings.
Eddie Butler, one of the Rockies' top prospects, came on in relief and allowed a go-ahead two-run home run to Danny Dorn in the fourth. Butler completed two innings, allowing four hits.
Butler, while not consistently sharp, reached 98 mph with his fastball. Righty bullpen hopeful Jorge Rondon, claimed from the Cardinals during the winter, topped out at 97 mph.
D-backs Cuban free-agent sign Yasmany Tomas was 0-for-3 at the plate. In the field, he made four nice plays at third and mishandled one to his backhand side.
Rockies up next: Righty Kyle Kendrick, who spent the last eight years with the Phillies, makes his Rockies Cactus League debut against the Angels at Tempe Diablo Stadium on Friday at 1:10 p.m. MT. Also on the pitching schedule is righty David Hale, obtained in an offseason trade with the Braves. Fans can watch a live stream on MLB.TV.
Steve Gilbert is a reporter for MLB.com. Read his blog, Inside the D-backs, and follow him on Twitter @SteveGilbertMLB. This story was not subject to the approval of Major League Baseball or its clubs.